The story revolves around a mysterious series of warehouse robberies perpetrated by a gang of clever thieves who have an inside contact with an international importing fir and, thusly, are tipped about the movement of valuable goods. The famous police dog, Tarzan, aids his master, Dan Kennedy, in uncovering and trapping the criminals, who finally meet justice head-on when the ambulance they've been using to carry their stolen loot crashes into a police station.